2

Dopamine:
Dopamine is a naturally produced compound synthesized in the adrenal medulla. It has many functions, including neurotransmission, cardiovascular maintenance, and it has effects on kidney blood flow. It is sometimes administered by a physician in situations where a person is critically ill and is needed for cardiovascular support.
...Read more

3

Yes:
Yes, only dopaminergic neurons release dopamine, but there are several dopaminergic pathways in the brain. Dopaminergic neurons in midbrain are the main source of Dopamine in the mammalian cns. Losing these is associated with parkinson's disease. Dopamine neurons are involved with voluntary movement and other behavioral processes such as mood, reward, addiction, psychosis, and stress.
...Read more

5

Most food sources:
Dopamine by itself is not found in any food sources but there are two Amino Acids that are converted to Dopamine in the body. Look for foods with phenylananine and tyrosine in them, though this is not very difficult to find. Most meats, dairy, and grains are high in both of these amino acids.
...Read more

11

Meds and motivation:
Antipsychotic meds used primarily for serious psychiatric disorders can help motivation as they improve disordered thinking, delusions and hallucinations. People who no longer have psychotic symptoms tend to function better and are more motivated overall. I hope this helps.
...Read more

15

What does use mean?:
The brain makes all of its DA. DA made outside the brain doesn't cross the blood-brain barrier so doesn't get into the brain. DOPA does cross the blood-brain barrier but ingested DOPA causes intractable nausea & vomiting if not given with carbidopa. Then there are dopamine agonists. Are you referring to those?
...Read more

No evidence:
Dopamine is increased by smoking however although in theory a good question not used options are nicotine replacements varencline nortriptine bupropion etc
the risk of side effects is not worth the risk since it is not a first line treatment.
...Read more

18

Root cause:
While it is important to understand all options available for parkinson's treatment, looking for the underlying causes and trying to treat those can help the symptoms and slow the progression of the disease. Parkinson's is a neurodegenerative disease, which is affected by genetics, toxins, nutritional deficiencies and lifestyle. These factors need to be evaluated and then addressed.
...Read more

19

Most newer ones:
Most of the newer antidepressant medications affect specific neurotransmitters. Each does it slightly differently, accounting for the different response rates amongst them.
The SSRI's primarily increase serotonin, the SNRI's both serotonin and norepinephrine, and buproprion mostly norepinephrine alone, and Brintellix affects many of them in different ways and in different places in the brain.
...Read more